Check for Suite B support using method flags instead of version numbers:
anything supporting TLS 1.2 cipher suites will also support Suite B.
Return an error if an attempt to use DTLS 1.0 is made in Suite B mode.
If we successfully match a cookie don't set return value to 2 as this
results in other error conditions returning 2 as well.
Instead set return value to -2 which can be checked later if everything
else is OK.
Add new methods DTLS_*_method() which support both DTLS 1.0 and DTLS 1.2 and
pick the highest version the peer supports during negotiation.
As with SSL/TLS options can change this behaviour specifically
SSL_OP_NO_DTLSv1 and SSL_OP_NO_DTLSv1_2.
Since s->method does not reflect the final client version when a client
hello is sent for SSLv23_client_method it can't be relied on to indicate
if TLS 1.2 ciphers should be used. So use the client version instead.
Add DTLS1.2 support for cached records when computing handshake macs
instead of the MD5+SHA1 case for DTLS < 1.2 (this is a port of the
equivalent TLS 1.2 code to DTLS).
Add correct flags for DTLS 1.2, update s_server and s_client to handle
DTLS 1.2 methods.
Currently no support for version negotiation: i.e. if client/server selects
DTLS 1.2 it is that or nothing.
Since this is always called from DTLS code it is safe to assume the header
length should be the DTLS value. This avoids the need to check the version
number and should work with any version of DTLS (not just 1.0).
Use the enc_flags field to determine whether we should use explicit IV,
signature algorithms or SHA256 default PRF instead of hard coding which
versions support each requirement.
Revise DTLS code. There was a *lot* of code duplication in the
DTLS code that generates records. This makes it harder to maintain and
sometimes a TLS update is omitted by accident from the DTLS code.
Specifically almost all of the record generation functions have code like
this:
some_pointer = buffer + HANDSHAKE_HEADER_LENGTH;
... Record creation stuff ...
set_handshake_header(ssl, SSL_MT_SOMETHING, message_len);
...
write_handshake_message(ssl);
Where the "Record creation stuff" is identical between SSL/TLS and DTLS or
in some cases has very minor differences.
By adding a few fields to SSL3_ENC to include the header length, some flags
and function pointers for handshake header setting and handshake writing the
code can cope with both cases.
Note: although this passes "make test" and some simple DTLS tests there may
be some minor differences in the DTLS code that have to be accounted for.
Add DTLS record header parsing, different client hello format and add
HelloVerifyRequest message type.
Add code to d1_pkt.c to send message headers to the message callback.
The version check for DTLS1_VERSION was redundant as
DTLS1_VERSION > TLS1_1_VERSION, however we do need to
check for DTLS1_BAD_VER for compatibility.
PR:2984
MD5 should use little endian order. Fortunately the only ciphersuite
affected is EXP-RC2-CBC-MD5 (TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5) which
is a rarely used export grade ciphersuite.
(cherry picked from commit f306b87d76)
Kludge alert. This is arranged by passing padding length in unused
bits of SSL3_RECORD->type, so that orig_len can be reconstructed.
(cherry picked from commit 8bfd4c659f)
Break dependency on uint64_t. It's possible to declare bits as
unsigned int, because TLS packets are limited in size and 32-bit
value can't overflow.
(cherry picked from commit cab13fc847)
We have to use EVP in FIPS mode so we can only partially mitigate
timing differences.
Make an extra call to EVP_DigestSignUpdate to hash additonal blocks
to cover any timing differences caused by removal of padding.
(cherry picked from commit b908e88ec1)
The previous CBC patch was bugged in that there was a path through enc()
in s3_pkt.c/d1_pkt.c which didn't set orig_len. orig_len would be left
at the previous value which could suggest that the packet was a
sufficient length when it wasn't.
(cherry picked from commit 6cb19b7681)
This patch makes the decoding of SSLv3 and TLS CBC records constant
time. Without this, a timing side-channel can be used to build a padding
oracle and mount Vaudenay's attack.
This patch also disables the stitched AESNI+SHA mode pending a similar
fix to that code.
In order to be easy to backport, this change is implemented in ssl/,
rather than as a generic AEAD mode. In the future this should be changed
around so that HMAC isn't in ssl/, but crypto/ as FIPS expects.
(cherry picked from commit e130841bcc)
This change adds CRYPTO_memcmp, which compares two vectors of bytes in
an amount of time that's independent of their contents. It also changes
several MAC compares in the code to use this over the standard memcmp,
which may leak information about the size of a matching prefix.
(cherry picked from commit 2ee798880a)
Trevor
Dr. Stephen Henson
Adam Langley
Trevor
Andy Polyakov
Michael Tuexen
Ben Laurie
David Woodhouse